immune system Flashcards
antigens
particles the body recognizes as not self and attacks
- induces an immune response
antibodies
initiate immune response in response to engaging with antigens
antibody structure
2 light chains and 2 heavy chains ,
- light chains linked by disulfide bonds
light chains contain highly variable region for antigen recognition
epitope
specific site on an antigen that binds tothe antibody
major histone compatibility complexes
class 1 and 2, present antigen fragments to t cells
MHC class 1 molecules
expressed in plasma membrane of all nucleated cells
- present t cells with antigen
- internal checkpoint, mutations associated with cancer
MHC class 2 molecules
macrophage and phagocytic cells like dendritic cells and B cells
- source of external information
- present foreign antigens to helper T cells
antigen presentation
cells present antigens on their membranes
- mhc molecules present
ELISA
immunostaining and visualizing specific proteins, specifical antibodies
innate immune system
broad spectrum defense that does not involve recognitiion of specific foreign compunds
cellular components of innate immune system
white blood cells
skin
major organ and barrier for innate immune system
what part of the imune system does the microbiota work under
innate
neutrophils
most common type of white blood cell
-phagocytise bacteria
acute inflammation response
- about 60% of WBC
lymphocyte
about 30% of circulating WBC
b cells, t cells and NKC
Nk cells
part of innate immunity, attack cancer cells
monocytes
about 5% of circualting WBCs
- differentiate into macrophages and dendritic cells
dendritic cells
antigen presenting cells in the skin
eosinophils
WBC target parasitic infections
basophils
invovled in allergy response
- histamine and heparin
opsonization
protein casacade that recruits phagocytes to engolf pathogen
compliment system
the activation of inflammation; (2) the opsonization (labeling) of pathogens and cells for clearance/destruction; (3) the direct killing of target cells/microbes by lysis.
cytokines
diverse class of signaling molecules involved in inflammatory response
IL-1 family
cytokines linked to temperature control, liver enzyme synthesis, cell based immunity, neuroinflammation
interferons
subset of cytokines with antiviral effects
inflammation
response to cellular injury,and innate immune response with macrophages and neutrophils
- vasodilation allows movement of WBC
types of adaptive immunity
humoral and cell mediated
humoral adaptive immunity
think B antiBody
- b cell learns to recognize pathogen and secrete antibodies in repsonse
b cells
precursors to antibodies
produced in bone marrow
potential fates of activated B cells
become plasma cells that secrete antibodies
become memory cells
plasma cell
activated form of a B cell that secretes antibodies
cell mediated adaptive immunity
t cells respond to antigens presented by MHC1 and MHC2 molecules
cytotoxic CD8 cells
recognize antigens presented by MHC1 molecules
- inject target with toxin to initiate apoptosis
CD4 helper T cells q
recognize antigens presented by MHC2 molecules
- secrete cytokines
supressor t cells
decrease cell mediated immunity after immune response is completed to avoid self reactivity
where are T cells produced? where are they matured
produced in bone marrow
stored and matured in thymus
positive selection
T cells that fail to recognize mhc1 and mhc2 molecules are eliminated
negative seelction
T cells that are over reactive against self cells are eliminated
what occurs in the bone marrow
hemoatpoesis
- production of blood cells (RBC, WBC, t cell, b cell)
lymphoid stem cells
differentiate into lymphocytes (b cells, T cells, NK cells
myloid stem cells
all other WBC
spleen
breaks down RBC,
lymph nodes
strorage of b and t cells